Ribbon spool construction



April 7, 1959 A. HEINRICH ET AL 2,

RIBBON SPOOL CONSTRUCTION Filed Sept. 11, 1957 2 Sheets-Sheet 1 Fig. I

INVENTORS HENRY A. HEINRICH NEIL S. WATERMAN a TTOR EYS April 7, 1959 H. A. HEINRICH ET AL 2,889,841

RIBBON SPOOL CONSTRUCTION 2 Sheets-Sheet 2 Filed Sept. 11, 1957 Fig. 3

Fig. 2

United States Patent RIBBON SPOOL CONSTRUCTION Henry Adam. Heinrich; Middlet'own, and Neil S. Watermam Stamford, Conn., assignors to Royal McBee Corgorzgron, Port Chester, N'.Y., a corporation of New Application September 11, 1957, Serial No. 683,261.

6 Claims. (Cl. 197-175) This invention: relates to. spools upon which are wound the ribbons utilized to transfer ink to paper in response to.- the actuation of type bars on typewriters or like printmg. machines; more particularly i'trelates to ribbon spools of the type which have support means for automatic ribbon reversing mechanism trip levers; and specifically it relates to an integral ribbon spool construction of the above-mentioned type which facilitatesthe assembly theretorofan automatic ribbon reversingmechanism trip lever in one operation;

As is well known a ribbon spool of the. above mentioned type generally comprises a. cylindrical core upon which a ribbon is wound and upper. and. lower circular flanges coaxially joined. to the core. for supporting and maintaining the edges of. the ribbon perpendicular to the axis of the core as it winds and unwinds. The lower flange: is usually formedwith a pair of downwardly depending lugs which are adapted to engagea toothed collar on: a ribbon spool drive shaft whereby the spool may be rotated. The lower flange is also provided with means for supporting a: ribbon reversing mechanism triplever. Bothmetal aud plastic ribbon spools are. presently inuse. The lower flange ofthe metal spools are usually die stamped whereby downwardly depending drive lugs and av pair of spaced perforated downwardly depending ears for rotatably supporting the-trip lever. are formed adjacent an. open area of the flange. In.- assembly a; mechanic is required to bend one or both of. said ears outwardly to enable insertion ofthe triplever pivots, to. mount a trip lever biasing spring on the trip lever,. and to thereafter. bend: the ears. backto: a position perpendicular to the plane of the flange whereby the trip lever is securely mounted to. the flange. The lower flanges of, the plastic spools presently in use areformed'in a mold; the formed flange including-the drive lugs. In accordance withpresent practice-a metalbracket havingapair of spaced perforated ears, whereby the trip lever is assembled tov the spool, must be screwed or riveted to the underside of the. flange by a mechanic, who-must thereafter perform the same operations. to assemble thetrip. lever thereto as those required in assembling a; trip lever to a metal spool. As is apparent from the foregoing, assembling a ribbon spool can be atedious and time consuming task.

In accordance with the present. invention an integral ribbon. spool construction is provided including a trip lever mounting formed integral with the-lower flange and core thereof, whereby a trip lever may be snapped into place and. securely held in operative position. Further in. accordance with: the present invention, the trip lever is so weighted that a, biasing spring is unnecessary to insure its. movement to an operativepositiom.

An object of the invention therefore is the provision of a novel ribbon spool; construction;

Another object of. the invention is the provision of an integral ribbon spool which is easily and inexpensively manufactured.

Another object of the. invention: is to, provide. an integral ribbon spool construction which facilitates the mounting of a ribbon reversing trip lever by unskilled persons without special tools. I

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A further object of the invention-is: toprovid'e a ribbon spool having an integrally formed ribbon reverse trip lever support which permits the trip lever to beeasily and securely snapped into: engagement with the spool.

Other objects and: many of the attendant advantages. of" this invention will be readily appreciated as thesa'm'e' he'- comes better understood by reference to the following detailed description when considered in connection with the accompanying drawings: in which like reference numera'ls designate like parts throughout. the figures thereof and: wherein:

Fig; 1. is atop planview' of the. novel ribbon-spook;

Fig. 2; is a cross: sectional view-taken along. lines: 2 -2 of Fig. 1;.

Fig. 3lis a.cross sectional: view taken along lines 3-3 of Fig. 1;

Fig. 4: is a perspective; view of a. ribbon reverse trip lever; and- Fig. 5 is'a view. similar; to Fig. 2 showing. the trip lever mounted on the novel:ribbon spool.

Referringnow'to the drawings there is, shown in Fig;v 1'. which illustrates a preferred embodiment, a ribbon: spool comprising a substantially cylindrical core generally designated by reference numeral 12. coaxially joined to a cirrcular flange. 13. In accordance with the invention the spool is formed from: anysuitable plastic,.e.g. polystyrene; although. it: is to be understood that the invention; may alsobe practiced withtspoolsformedof. any suitablemetal; The corev of the ribbon; spool; is. defined by anouter. wall 14: joined to an. inner cylindrical hub 15' by a: pluralityof? webs 16 radially extending equivalent distances. from the hub. The: outer wall 14- of. the: core is cylindrical. and concentric with the hub- 1-5 exceptfor a straightflat secs tion 17 between two of the. webs. Thestraight section of the core wall is relatively thinner than the rest of the wall 14, and as seen. in Fig. 3, the intersections of. the straight and cylindrical portions of the outer wall are defined by slots 18 extending predetermined distances: up.- ward from the lower surface 19' of; the flange. The cirs cular flange which is integrally joined to the core isformed with a cut away area.21-. (Figs; 1 and. 2) v defined by the area between the two. webs having between them the straight section 17 of. the core wall and a line 22' outwardly' parallel from the. plane of the straight section. The lower corners of the straight. wall sectionareformed with. two projections 23 which. extend down into. the. cut away area. and. then toward the. periphery of and parallel tov the plane offthe. bottom. surface of the flange; 19: for reasons which; will-hereinafter. appear. Diametrically opposite the straight wall section, the core: wall-1 is. formed with a slot 24, whereby the terminal. end: of a ribbon may be secured to the core.

As is apparent from the above, the straight section 17 of the core wall is free. to deflect toward the axis of". the coreupon application of force to the lower end of. the. straight section.

The underside of' theflange is formed with at leastctwo. spaced downwardly depending rectangular drivelugs ziand with two upwardly open semi-cylindrical. pivorho'nslugs 26 depending from the. bottom surface: 19 of the: flange; The axes 27 of the. pivot housings are disposedi on a line parallel with and between: the plane; of the straight section 1 7" and the. edge 22 of the cutout area: parallel to the plane of the straight. section. of the: core wall. The facing ends of the semi-cylindrical piivot housings 26 which are co-planar with the sides: 28; of. the cut way area areopen. as seen in Figs. 1 and 3 while the outwardly facing ends. are closed. As seen? tion of. the core wall extend over and: beyond the axes 27 of the semi-cylindrical pivot. housings 26.

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I Referring now to Fig. 4, there is shown a perspective View of the ribbon reverse trip lever 31. The trip lever comprises an upper and lower arm 32 and 33 respectively joined by a body portion 34. The lower arm 33 is spade shaped and perpendicular to the body portion 34 and the upper arm 32 is bent at a predetermined acute angle toward the lower arm. The body portion is made at least as wide as the width of the straight section of the core wall and is formed with pivots 35 extending from the top edge of the opposite sides thereof.

To assemble the spool the spade shaped arm 33 is forced down between the edge 22 of the cutout area in the flange and the projections 23 on the straight section 17. As seen in Figs. 2 and 5 the edges 22 and projections 23 are bevelled whereby upon insertion of the trip lever 31 the straight section 17 is deflected toward the axis of the core by a camming action. After the lowerarm 33 is pushed through, it is grasped on the underside, rotated toward the underside of the flange and pulled until the body portion 34 clears the projections 23 on the straight section of the core wall, whereupon the pivots 35 drop into the pivot housings 26 and the straight section 17 snaps back to normal. As is apparent in Fig. 5, the trip lever pivots are locked in the semi-cylindrical pivot housings 26 by the projections 23 after the straight section resumes its undeflected position. The trip lever 31 after being locked in is free to pivot to approximately 30 below the underside of the flange.

As is understood in the art the spool assembly is placed on a typewriter or like printing machine with the drive shaft within the cylindrical hub 15 of the core and with the lugs 25 depending from the flange in engagement with a toothed collar on the drive shaft whereby the spool assembly is rotated. A ribbon wound on the spool will retain the trip lever 31 in the dotted position as shown in Fig. 5 until the ribbon unwinds and frees the upper arm 32 of the trip lever whereupon the weight of the lower spade shaped arm 33 will cause the trip lever to drop to the position shown in full whereby it may actuate a member of a conventional ribbon reverse mechanism in its path. Actuation of the ribbon reverse mechanism will reverse the rotation of the now unwound spool causing the ribbon to rewind. As the ribbon rewinds on the core it will cause the upper arm of the trip lever to rotate back to its normal position adjacent the flat face of the straight wall action.

It should be understood, of course, that the foregoing disclosure relates to only a preferred embodiment of the invention and that it is intended to cover all changes and modifications of the example of the invention herein chosen for the purposes of the disclosure, which do not constitute departures from the spirit and scope of the invention.

The invention claimed is:

1. As an article of manufacture, a ribbon spool having a substantially cylindrical hollow core and a coaxially joined circular flange, said flange having an area cut therefrom having at least two parallel edges, a pair of aligned semi-cylindrical pivot housings oppositely formed in said parallel edges, said core being formed such that a wall section parallel to the axes of said pivot housings and oversaid area is resiliently deflectable toward the axis of said core, and projections on the lower corners of said wall section extending over and beyond the axes of said pivot housings, adapted in combination with said pivot housings to rotatably support a ribbon reversing mechanism trip lever.

2. As an article of manufacture, a ribbon spool of the type adapted to rotatably mount a ribbon reversing mechanism trip lever, said spool comprising a core comprising a substantially cylindrical outer wall and a circular flange coaxially joined to said core, said outer wall being characterized by at least one flat surface parallel to the axis .of the core, slots inthe' outer wall on either side of said fiat surface and extending predetermined distances from the plane of the flange, said flange being characterized by an open area extending beneath said flat surface, said flange being further characterized by a pair of semi-cylindrical pivot housings open to the upper surface of said flange and having a common axis parallel to the plane of said flat surface, said pivot housings being formed in opposite edges of said open area and outward of the plane of said flat surface, and projections on the lowermost corners of said flat surface extending over and beyond the axes of said pivot housings, adapted in combination with said pivot housings to rotatably support a ribbon reversing mechanism trip lever.

3. As an article of manufacture, a ribbon spool of the type adapted to rotatably mount a ribbon reversing mechanism trip lever, said spool comprising a core comprising a substantially cylindrical outer wall joined 0 a hub by spokes radiating from said hub and a circular flange coaxially joined to said core, two spaced slots in the outer wall of said core extending predetermined distances upward from said flange and defining between them a deflectable member, said flange being characterized by an open area extending beneath said member whereby it may be deflected, said flange being further characterized by aligned upwardly open semi-cylindrical depressions having a common axis formed in opposite edges of said open area outward of said member, and projections parallel to the plane of said flange and extending toward the periphery of said flange formed on the lower corners of said member, said projections on said member extending over and beyond the axes of said depressions.

4. As an article of manufacture, a ribbon spool having a substantially cylindrical substantially hollow core and a coaxially joined flange, said flange being characterized by an open area and a pair of aligned upwardly open semi-cylindrical depressions in opposite sides of said area, said core being characterized by at least one flat wall section partially separated from the remainder of the core wall by a pair of spaced slots perpendicular to the plane of the flange, the plane of said flat wall section being parallel to the axis of said depressions and disposed over said area, and means projecting outwardly from the lower corners of said flat wall section extending over and beyond the axes of said semi-cylindrical depressions.

5. A ribbon spool assembly comprising a ribbon spool having a substantially hollow core and a coaxial flange, a ribbon reversing mechanism trip lever, and cooperating means integrally formed with said core and flange respectively, said trip lever comprising a pair of pivots, said cooperating means on said core comprising a resilient member, and said cooperating means on said flange comprising a pair of trip lever pivot housings parallel with the plane of and below said resilient member, said resilient member being adapted to deflect to allow insertion of said trip lever pivots into said housings and thereafter to resume its undeflected position after the insertion of said trip lever pivots thereby to maintain said trip lever securely mounted for rotation.

6. A ribbon spool assembly comprising a ribbon spool having a substantially hollow core with a coaxial flange, a ribbon reversing mechanism trip lever having a pair of pivots, pivot housings integrally formed on said flange, and resilient means integrally formed with said core for enabling the trip lever pivots to be inserted in and maintained in said pivot housings.

References Cited in the file of this patent UNITED STATES PATENTS 777,282 Ford Dec. 13, 1904 1,194,979 Etheridge Aug. 15, 1916 FOREIGN PATENTS 133,257 Great Britain Oct. 9,1919 

